Electric starter system



Patented Apr. 12 1938 UNITED STATES ELECTRIC STARTER SYSTEM Bennett M.Leece, Shaker Heights, Ohio, assignor to The Leece-Neville Company,Cleveland, Ohio,

a corporation of Ohio Application November is, 1935, Serial No. 50,294

6 Claims.

This invention relates to electric control apparatus, and moreparticularly to control apparatus which is useful in connection with thestarting motors of internal combustion engines and in connection withvarious other motors and electrical equipment.

An object of the present invention is to provide improved electricalcontrol apparatus embodying novel means for preventing sticking ofswitch contacts.

Another object of this invention is to provide improved electric controlapparatus wherein a magnetically actuated member is arranged to causeopening of switch contacts to overcome l5 sticking thereof.

A further object'of this invention is to provide improved controlapparatus wherein a magnet actuated member is arranged to cause openingmovement of switch contacts to overcome stick- 20 ing thereof, andwherein the energizing circuit for the magnet is established through thesticking contacts.

Still another object of this invention is to provide electric controlapparatus wherein a switch controlled magnet causes closing of a-pair ofcontacts when energized and permits opening of the contacts whendeenergized, and wherein a magnet operated striker causes opening of theswitch contacts to overcome sticking thereof, the circuit for thestriker magnet being established through contacts of the switch andthrough the sticking contacts.

It is also an object of this invention to provide an improved electricstarter system comprising a switch with a manually operable membernormally held in an initial position but movable to a second position, amagnet which is energized to close a pair of load contacts when themanually operable switch member is in its second position, and a magnetactuated striker which acts to overcome sticking of the load contactsand which is energized whenever the switch member is in its initialposition and the load contacts are closed.

Other objects and advantages of the invention will be apparent from thefollowing description when taken in conjunction with the accompanyingsheet of drawings, wherein Fig. 1 is a diagrammatic view illustrating anelectric control system embodying my invention; 50 and Fig. 2 is adiagrammatic view showing a similar but a somewhat simplified controlsystem.

The electric control system of my invention may be applied to varioususes but is especially useful in connection with electric startingmotors of the kind commonly used for cranking internal combustionengines. While the control systems shown in the drawing will behereinafter described in connection with electric starting apparatus, itshould be understood, however, that 5 my invention is not necessarilylimited to this particular field'of use.

In the control system illustrated in Fig. l of the drawing, I have shownan electric motor Iii, which may be the driving motor of an electric 1ostarter device, and a source of energizing current for the motor, suchas a storage battery H. A manually operable switch l2 establishescircuit connections which, as will be presently explained, cause thedesired operation of the starting motor Ill. My control system alsoincludes a magnetically operated switch or contactor l3 in the motorcircuit and a magnetically actuated device H for overcoming sticking ofthe contacts of the latter switch.

The control switch l2 may be of any construction suitable for theservice which it is to perform. For example, as shown in the drawing,this switch may comprise a suitable insulating base it provided'with aplurality of stationary contacts ll, l8, i9, 20, and 2!, and a movablecontact 22 which may be actuated by any suitable manually operablecontrol, such as the hand lever 23 extending from the switch base. Thehand lever 23 is operably connected with a barrel or sleeve 24 5 whichcarries the contact 22 such that by manipulation of the hand lever thecontact will be moved or swung into engagement with different sets orpairs of the stationary contacts. The switch base may be. provided witha pivot pin or shaft 25 on which the sleeve 24 and the hand lever 23 aresuitably mounted.

The contact 22 may be in the form of a metal rim which is mounted upon aroller 26 formed of insulating material. This roller is rotatablycarried by a block 21 which is slidabie in the sleeve 24 and is normallyurged outwardly thereof by a coil spring 28. The stationary contacts ofthe switch l2 are preferably disposed in arcuate arrangement, as shownin the drawing, 'so that when the sleeve 24 is swung about the pivot 25by means of the handlever 23, the contact 22 will roll over thestationary contacts.

The stationary contacts shown in this instance are sufiicient in numberto provide three different 60 stations or positions for the movablecontact 22. The first or initial position of the movable switch contact22 is indicated by the line 30, and when the contact is moved to thisposition, it electrically connects the stationary contacts I1 and I8.

I The second position for the movable contact 22 tween the contacts I8and'28 as it passes thereover.

As will appear more fully hereinafter, it is important in the operationof my controlsystem that the movable switch contact 22 be normally heldin or returned to the position 38 so as to electrically connect thecontacts l1 and i8. To'this end I provide suitable means, such as thecoil spring 35, which is disposed around the pivot pin 25 with one endthereof engaging a projecting part 38 of the sleeve 24 and the other endthereof anchored on a projecting part 31 of the contact |1. reason ofthe spring arrangement shown and described, it will be seen that thecontact 22 is normally held in engagement with the contacts l1 and i8but is movable from this initial position to the positions 3| and 32. Ifdesired, a suitable stop 38 may be provided adjacent the contact 2| toprevent movement of the contact 22 beyond a predetermined point.

When the hand lever 23 is operated to move the contact 22 from theposition 38 to the position 3|, the contacts I8 and I9 are electricallyconnected to establish a low voltage energizing circuit for the motori8. By means of the circuit thus established, current is supplied to themotor from the battery II at a low voltage, for example, six to eightvolts. This energizing circuit may be traced as follows: From terminal48 of the battery II through conductor 4| to motor l8, then throughconductors 42 and 43 to switch contact I8 4 and through movable contact22 to stationary contact l9. and then back to the terminal 44 of thebattery through the conductor 45.

When the switch member 22 is moved to the position 32 by'furtherswinging of the hand lever 23, the contact 22 connects contacts 28 and2| and causes energization of the magnetic switch or contactor |3 toclose the load contacts 41 and 48. The closing of these load contactsestablishes .another circuit for the starting motor |8 whereby currentis supplied to the motor at a relatively higher voltage, for example,thirty-two volts. When this circuit has been maintained long enough forthe starting motor I8 to perform its function, the hand lever 23 isreleased and the movable contact 22 is immediately returned to theposition 38 by the action of the spring 35. This second energizingcircuit for the motor may be traced as follows: From battery terminal 48through conductor 4| to the motor In, and then through conductors 42 and49 to the stationary load contact 41, then through movable contact 48and the frame or body of the magnetic switch l3, and then back to theterminal 58 of the battery through conductor 5|.

The magnetic switch or contactor may be of any suitable construction,and, as shown in the drawing, may have a frame 52 which carries themagnet 53 and the movable armature 54. The frame 52 may be provided witha pivot or hinge pin 55 upon which the armature 54 is mounted to swingtoward and away from the magnet 53. The

load contact 48 may be carried by the armature 54 and mounted thereon bymeans of a projecting flexible metallic arm or spring 56. The armature54 may be acted upon by a weight 51 or the equivalent thereof to causethe same to swing on the pivot 55 in a direction to normally hold thecontacts 41 and 48 open when the magnet 58 is deenergized.

The coil of the magnet 53 of the contactor l3 has a lead 58 at one endthereof which is connected to the switch body or frame and the other endof this magnet coil is connected to the stationary contact 2| of theswitch |2 by means of the conductor 58. By reason of these connectionsfor the magnet coil 58, it will be seen that when the switch contact 22is moved into engagement with the stationary contacts 28 and 2| themagnet 53 is energized to cause closing of the load contacts 41 and 48.The energizing circuit for the magnet 53 may be traced from the batteryterminal 48 through conductor 4|, conductor 58' to stationary switchcontact 28, then through movable switch contact 22 and stationarycontact 2|, and through conductor 59 to the magnet coil 58 and thencethrough conductor 58, the body of the switch l3, and back to batteryterminal 58 through conductor 5|. It will be noted from the circuitsabove traced that when the magnet 53 is energized by movement of theswitch member 22 to its position 32, the high voltage energizing circuitfor the starter motor I8 is then established through the load contacts41 and 48 of the contactor and not through any of the contacts of theswitch l2.

When the hand lever 23 is released, the movable contact 22 is returnedto the position 38, as explained above, and the energizing circuit forthe magnet 53 is broken. Normally, the deenergization of the magnet 53allows the contact 48 to be moved away from the contact 41 by the actionof the weight 51 and of the spring arm 56. However, in spite of the useof special alloys for the contacts 41 and 48, it is found that theyirequently stick together and the energizing circuit for the motor I8 isnot broken when it should be. To overcome this difllculty, I haveprovided the electromagnetic device I4 for causing positive opening ofthe load contacts 41 and 48. The device l4 may be of any suitableconstruction and may comprise a magnet coil or solenoid 88 with amovable core 6| arranged therein to cause a striker 62 to be projectedthrough a guide member 83 whenever the solenoid or magnet coil isenergized.

The core and striker may be retracted upon deenergization of the coil68, as by means of a suitably arranged spring 64. When the striker 62 issuddenly projected by energization of the coil 68, it strikes theextension 65 of the spring arm 56 and thereby causes the movable contact48 to be moved away from the contact 41 to open the motor circuit.

The energizing circuit for the magnet of the device I4 is so arrangedthat it will be closed when the contact 22 of the switch I2 is returnedto its position 38, provided the load contacts 41 and 48 remain closed.If the load contacts 41 and 48 are opened upon deenergization of themagnet 53, as they normally should be, the magnet 88 will not beenergized when the contact 22 returns to its position 38. However, ifthe contacts 41 and 48 stick, the magnet 88 will be energized to causeoutward movement of the striker 82 as soon as the contacts I! and i8 arebridged by the contact 22. The energizing circuit for the magnet 88 maybe traced as follows: From battery terminal 48 through conductors 4| and66 to the magnet coil,

' and then through conductor 61 and contact strip 8 to the stationarycontact [1 of the switch i2, then through movable contact 22, stationarycontact i8, load conductors 48 and 49, load contacts 41 and 48, andthrough arm 56 and the body of switch l3, and then back to batteryterminal 58 through conductor In Fig. 2 of the drawing I have shown myinvention embodied in another control system which is of somewhatsimpler form. This control system also includes a motor 18, which may bea motor for starting an internal combustion en-.

glue, and a storage battery ll for supplying energizing current to themotor. A pair of load contacts 12 and 18 control the motor circuit andwhen closed cause the motor to be driven by current supplied .from thebattery. The opening of these contacts opens the motor circuit.

The load contacts 12 and 13 are closed by ener gization of the magnet llof the contactor or eiectromagnet switch I5. Contact I3 is carried on aspring arm I6 which is in turn carried by the armature ll of theelectromagnetic switch. The armature Il may be hinged to the frame 18 ofthe electromagnetic switch by means of the hinge or pivot pin 19. Thespring arm 16 has a part 88 projecting beyond the contact 13, and thisprojecting part is adapted to be engaged by a striker II in the eventthe contacts 12 and 18 remain closed after deenergization oi the magnet14. The striker 8| may be carried by a movable core 82 disposed within amagnet coil or solenoid 83 which is arranged to be energized wheneverthecontacts l2 and 13 remain closed as the result of sticking.

A manually operable starting switch 84 controls the energization of themagnets 14 and". This switch may have a pair of stationary contacts 85and 86 representing first and second positions for a. manually movableswitch contact or arm 81. The contact 81 is normally held in, orreturned to, its first or initial position in engagement with thecontact 85 by means of a tension spring 88.

When the internal combustion engine is to be cranked, the switch member81 is moved into engagement with the contact 86 and, by reason of thecontrol circuit therebyestablished, the magnet I4 is energized andcauses closing of the load contacts I! and 13. The closing of thesecontacts causes the motor 18 to be operated by current supplied from thebattery 1i. When the switch member 81 isreleased, it is returned to itsinitial position in engagement with the contact 85 and thedeenergization of the magnet 14 by the opening of the circuit thereof atthe contact 86 permits the contacts 12 and 13 to be opened by theswinging of the armature 11. However, if the contacts 12 and 13 remainclosedJor example as the result of sticking, the magnet '83 is energizedto cause the striker 8i to suddenly engage the arm part 80 and open theload contacts. The energizing circuit for the magnet 88 is' establishedthrough the contacts 85 and 81 of the switch 84 and through the contactsI! and 13 when the latter remain closed. v I

It will be noted that in both of the control systems disclosed in thedrawing the magnetically operated striker engages a part of the armatureof the magnetic switch at a point relatively remoteirom the armaturepivot or hinge. With this arrangement, the lever arm is such that only alight suddenly acting force need be applied to the armature to causeopening of the contacts in overcoming sticking thereof. I find thatopening of the load contacts can be accomplished by use of a relativelysmall magnet for actuating the striker and that the use of such amagnetically operated striker permits the magnetic switch for operatingthe load contacts to be of much simpler and lighter construction thanwould otherwise be the case. It will be observed, furthermore, that theoperation of the striker is dependent upon a circuit established throughcontacts of the starter switch and also through the sticking loadcontacts, and that this arrangement provides for the energization of thestriker magnet automatically and onlv in'the event that the loadcontacts stick.

While I have described my improved control apparatus in a somewhatdetailed manner, it will be understood, of course, that I do not wish tobe limited to the precise arrangements described and illustrated in thedrawing, but regard my invention as including such changes andmodifications as do not involve a departure from the spirit of theinvention and the scope of the appended claims.

Having thus described my invention, I claim:

1. In combination, a circuit, a pair of contacts in said circuit, amagnet adapted to close said contacts when energized and to permitopening of said contacts when deenergized, a circuit for said magnet, aswitch having contacts controlling the magnet circuit, and magneticallyoperable means for opening said contacts in the event of stickingincluding a circuit established through contacts of said switch andthrough the sticking contacts.

2. In electricstarting apparatus, the combination of a motor, a loadcircuit therefor, a pair of load contacts in said circuit, a magnetadapted to cause closing of said load contacts when energized and topermit opening thereof when deenergized, a circuit for said magnet, aswitch having contacts controlling said magnet circuit, a member movableto cause opening of said load contacts, a magnet for actuating saidmember, and a circuit for the last mentioned magnet adapted to beestablished through contacts of said switch and through said loadcontacts.

3. In electric control apparatus, the combination of a load circuit, apair of contacts in said circuit, a magnet adapted to cause closing ofsaid contacts, a second magnet adapted to cause opening of saidcontacts, circuit connections for said magnets, and a switch having oneposition for energizing the first mentioned magnet andanthereof, a.magnet for actuating said member, a

switch having a member normally held in one position but movable to asecond position, circuit connections for energizing the first mentionedmagnet when the switch member is in said second position, and circuitconnections for energizing the second mentioned magnet when the switchmember is in said one position and said load contacts are closed.

b. In electric starting apparatus, the combination of a motor, a motorcircuit, load contacts in the mot r circuit, a magnet having a movablearmature carrying one of said load contacts and adapted to cause closingof said contacts when energized, a striker adapted to engage saidarmation of a motor, a battery having terminals affording differentvoltages, a starting switch having a member normally held in an initialposi-.

tion but movable to second and third positions. connections providing alow voltage load circuit for the motor when the switch member is in saidsecond position, connections providing a high voltage load circuit forthe motor, a pair of contacts in the high voltage load circuit, a magnetadapted to close said contacts when energized, connections forenergizing said magnet when said switch member is in said thirdposition, a magnet adapted to open said contacts when energized, andconnections for energizing the last mentioned magnet when the switchmember is in said initial position and said contacts of the high voltageload circuit are closed.

BENNETT M. LEECE.

